This year, the world's best-known climate activist,
Greta Thunberg, turned 18.
People say a lot of things about me.
Greta... You know Greta?
CROWD BOOING
People call me a brat, an idiot.
And yet, for reasons I don't understand, people listen
when I talk.
CROWD CHEERS
You are listening to me right now.
But I don't want that. I don't want you to listen to me.
I want you to listen to the science.
We are seeing a huge change in the temperature of the planet.
Wildfires and floods and droughts and super storms around the world.
That's where we're headed if we don't take action.
This series follows Greta on an extraordinary year in her
fight against climate change.
I'll be going halfway round the world, the wrong way.
In 2019, she took a year off school to witness first-hand
the impact of global warming...
As soon as the ice in the rock starts to get warmer,
that stabilising influence disappears.
..and discover whether technology could help protect our future.
We could store all the emissions we could potentially imagine.
We should be hopeful, but hope doesn't come from words.
Hope only comes from action.
Unless we do something, we're going to lose everything.
Greta's taken her protest to the global stage.
World leaders are behaving like children,
so it falls on us to be the adults in the room.
But in a year when Covid brought life to a standstill...
The coronavirus continues to spread.
..can Greta convince a world reeling from one crisis
to finally face another?
Covid-19 has given the world a tremendous opportunity to reset.
How we address the climate crisis will determine
what the future of life on Earth looks like.
We can act...
..but we don't have time to wait.
January 2020.
The most powerful people in the world are preparing
to gather in Davos, Switzerland, for the 50th World Economic Forum.
And they've invited Greta, who plans to use the opportunity
to persuade them to abandon fossil fuels.
It's the next step in a remarkable journey that's taken her through
North America, where she witnessed climate change first-hand...
We think of glaciers as great and powerful, but in fact,
we know we're not bringing this glacier back.
..back across a stormy Atlantic, to the main stage
of the United Nations Climate Summit in Spain.
We no longer have time to leave out the science.
After time at home in Sweden, Greta is travelling north
to the edge of the Arctic Circle
to see for herself the human cost of global warming.
The Sami people, they're actually Europe's last
and only indigenous people.
They have a very rich culture and traditions.
Because of the changing climate,
their way of life is being threatened.
Indigenous Sami herders, like Carl-Johan Utsi and Sanna Vannar,
have been caring for reindeer for over 1,000 years.
What does the reindeer mean to you and to the people here?
It's so important for us, with nature and also with animals.
We get everything from the reindeer.
We get the antlers and the skins and the meat,
but mostly it is a way of living and a way of life.
But now, the reindeer are facing starvation.
So why is climate change making
it harder for the reindeer to find food?
This lichen grows naturally in the forest area.
That's the main food for the reindeer in winter time.
The snow could easily be one metre deep,
but the reindeer still can find it by smelling it through the snow
and digging it up with their hooves.
But this year, we have to give them extra food
because the natural food is beneath hard-packed snow and ice.
Close to the poles, temperatures are rising faster than anywhere else on
Earth, and warmer temperatures mean it often rains when it used to snow.
When the rain hits the cold ground, it forms a layer of ice,
which the reindeer can't break.
What would happen to these reindeers
if you weren't here to give them this...?
They would spread out on the huge area and a lot of them
would die from starvation.
If these pressures continue, many Sami may be forced to
abandon herding, and this unique way of life could be lost forever.
I hope that the next generation can still have a life
with the reindeers.
We have been following the reindeer for thousands of years
and we don't want to give up just yet.
The climate crisis is a very unfair crisis.
It is the ones who are already the most vulnerable that are going
to suffer the most.
Around the world, we are already starting to see human
migration due to climate change and it's only going to accelerate.
My country, Bangladesh, is now being hit by both cyclones,
as well as floods, and in the longer term,
sea level rise.
So I would estimate that the number of people being forced to move
is very credibly going to go up to hundreds of thousands -
and indeed millions, perhaps - over the next ten to 20 years.
If you look at Africa, for example,
you're already seeing desertification.
People will have to move away from places
where they can no longer live, which might create conflict.
Those who cannot move may well perish where they are.
We can adapt to some of this,
but the scale is such that we cannot adapt to it all.
The real injustice of this is that these are people who have
contributed often the absolute least.
They have not been the ones burning tonnes of fossil fuel,
but they are bearing the brunt of the impacts of climate change.
Greta is setting off on a journey that will take her
to the World Economic Forum in Davos.
There, she will demand an immediate reduction in fossil-fuel use,
putting pressure on world leaders -
particularly US President Donald Trump.
Greta usually travels with her father, Svante,
but for the first time, she'll be going without him.
She's become like an adult now.
She was, you know, a child when she started this and...
..now she's much more of an adult, yeah.
You know, she doesn't want me around as much, which is great.
This is her thing. Now she's old enough to do it by herself.
Greta won't be completely alone.
A family friend is travelling with her.
But for Greta, it's still a big step.
Now I'm 17, I had my 17th birthday.
I celebrated with a strike,
as usual, outside the Swedish parliament.
Soon, I'm officially an adult, 18 years... Yeah.
No, I don't like that.
MUSIC
Of course, I want to become more independent, but also want to
remain a child because life is so simple when you're a child.
Thanks!
The effects of climate change are now being felt all over the world.
Thank you very much. Love what you're doing.
Here in Europe, increasingly severe weather is already wreaking
havoc in towns and cities.
Severe flood warnings are in place this
afternoon in parts of England, meaning there is a danger to life.
Heavy rain forced the river right through this town in Bavaria.
Parts of France have seen the same sorts of problems.
There's clearing up to do, and there's more rain to come.
To understand more about the causes of flash flooding,
Greta is stopping off in Gdansk, Poland.
She's here to meet a climatologist who studies extreme weather...
..Professor Jacek Piskozub.
Hi. Hello.
Nice to see you. I'm Greta. Nice to meet you.
Very nice to meet you, too.
In 2001, torrential rain led to floods across Gdansk.
How much higher was the water level?
All this, from this concrete channel to this building, were gone.
More flooding followed in 2016.
This is some footage from the last...
Floods.
To the climate crisis, you expect...
You expect melting glaciers
and you don't expect these kinds of events in this part of Europe.
What do you think could be the cause of these...these floods?
The main reason is that
the warmer it gets, the more water vapour it can hold.
You have something like 7% more water vapour per every degree
increase of temperature.
More water in the air means heavier, more extreme downpours.
Warmer temperatures are also affecting air currents,
driving more storms over Northern Europe.
In the future, is this what the pattern is?
Is this what we should be expecting?
Yes, we should prepare for, I should say, tropical rains here
because sooner or later
we will get temperatures in summers like in tropical countries here.
We see very strongly in Northern Europe this pattern of more
extreme rainfall and heavier rainfall
in cities, where the water can't really go anywhere
and that leads to flash flooding.
But, of course, there are other extreme weather events
for which climate change plays an important role.
Heatwaves are becoming more severe and more common.
In 2019, we had a heatwave across Europe, with temperature
records being broken in France, in Germany, in many other countries.
And we found that without climate change,
the heatwave in France would have been two degrees cooler.
And that cost lives.
The 2019 European heatwave caused
the deaths of around 2,500 people.
We've seen that just one degree Celsius of warming has led to
unprecedented extreme weather events.
That's just one degree Celsius - and we'll see far more than that
if we continue on the course that we're on.
Greta is travelling south, towards Poland's industrial heartland.
WEATHER FORECAST IN POLISH
It's the end of her first week on the road.
It's the first time I'm travelling without my parents.
I was expecting to be more, like, homesick, being away from home.
But I don't really feel like that. It's...
Which is good, of course.
I definitely feel that I've become more independent
and more capable of handling things and so on.
It was very strange to see her go off by herself.
It took a few days of getting used to, you know.
You check in all the time. "Are you OK?"
You know, "How are you feeling?"
And, of course, you don't think that they will survive
at all, without you there.
But of course, they do. They always do.
In 2015, world leaders agreed to a global treaty,
aiming to limit temperature rise.
Yet here in Poland,
80% of electricity is still generated by burning coal.
At the World Economic Forum, Greta will question
politicians on how they plan to deliver on their promises.
World leaders say that we will keep the global average
temperature rise to below 1.5 or well below 2 degrees,
and yet they still plan to continue burn coal for decades.
Coal is the most polluting of all the fossil fuels,
releasing almost twice as much carbon dioxide as burning gas.
To discover why it's still being used,
Greta is meeting Hanna Brauers,
who studies the impact of the coal industry.
Can you tell me a bit about this place?
Well, this is the biggest coal power plant in the entire EU.
In the whole of EU? Wow!
And also, it's the biggest carbon dioxide emitter,
so it emits about 38 million tonnes of CO2 each year. That's...
I mean, you cannot realise how much that is.
The Belchatow Power Station is built next to an opencast mine,
stretching eight miles across.
I've seen many coal power plants, but never one as big as this.
It's massive. It's just enormous. Yeah.
Why are we still so dependent on coal? We are we using it so much?
Compared to oil and natural gas, it's just easier.
Coal is relatively easy to get out of the ground, you can store
it very easily, and when you think about coal, it's very energy dense.
You simply burn it and you get a lot of energy.
And is it cheaper or more profitable to use coal?
So, short-term costs are very cheap,
but if you account for all the costs that coal has - climate cost,
environmental cost and also health cost for people -
I don't think it's cheaper in any part of the world.
The low cost of extracting coal means it's still
responsible for over a third of electricity generated worldwide.
We need a very rapid,
but carefully managed transition
away from fossil fuels to clean energy.
Nuclear may have a small role, as a very low-carbon electricity
source, but if you wanted to, say, get half of our energy from nuclear,
you'd have to have several thousand nuclear power stations
built in the next ten, 20 or 30 years.
So it's only when you play out the practicalities of the planning
issues and waste issues,
you start to realise it can't play a huge role.
The good news is that the answer here is very simple.
The miracle's already there.
It's the sun, it's the wind, it's geothermal.
There's a renewable energy supply for every country on the planet.
If you're in a windy country - like the UK, for example - we've got
really great wind resources.
If you're in a sunnier country, like India, then you're
going to have a lot of cheap solar power.
The thing that's so important about renewables -
and has changed, actually,
so much even in the last decade - is they've just become cheaper.
It has been dramatic
and they are now right across the world cheaper
than fossil-fuelled electricity supply.
Now, there's still some limitations
because the sun isn't always shining,
the wind isn't always blowing, so ultimately,
you need battery infrastructure, grid infrastructure,
that can integrate renewable energy more efficiently.
One of the big challenges to recognise
when we think about moving away from fossil fuels is that there are lots
of jobs and communities involved, to have locked in all this
infrastructure, and we have to rapidly move away from that.
We shouldn't underplay how difficult that is.
Before leaving Poland, Greta has come to the region of Silesia,
where coal has been mined for over 800 years.
We have many, many very easy solutions at hand right now,
like moving from fossil fuels to renewable energy,
but people desperately want to keep the status quo.
We will go down.
She's meeting a few of the thousands of miners who lost their jobs
when their pit was closed in 2016.
Falling coal prices
and rising costs meant they could no longer turn a profit.
Many in the region fear a shift towards renewables will lead
to even more job losses.
I wanted to go to talk to the coal miners in Poland to see
things from a different perspective and to sort of see the human
implications that the transition might bring.
Could you tell me a bit about how you felt
when you first heard that the mine was closing?
You've obviously contributed so much to the society
and then they just close it like that.
I mean, you must have felt very betrayed.
I think I was a bit nervous before
because I thought they probably see me as some kind of angry
teenager, but I think it is important to listen to...
..to these people say what they have to say.
Honestly, I was positively surprised that they were so aware
and they said, "Yes, we want a sustainable transition,
"but it has to be in the right way."
If we are to address the climate crisis,
we need to fundamentally change what we prioritise.
And, of course, we need the political will
to actually care for and prioritise people and the planet,
so that we won't leave anyone behind.
Greta is preparing to take this
message to the World Economic Forum, now just a few days away.
Key figures from industry, world leaders - even a few celebs -
all descending on the Alpine ski resort of Davos for this year's
World Economic Forum.
Attending this year will be President Trump,
teenage climate activist Greta Thunberg and top executives.
The reason a Swedish schoolgirl has gained the attention
of prime ministers and presidents is because her school strikes
have become a global movement.
When I started striking, I didn't know what it could lead to.
I just thought that I need to do something
and I hope it has any effect.
Today, when she attends a march, tens of thousands
flood the streets, and millions more follow her updates online.
This is week 74.
Marches are my thing. That's what I do.
But it's actually very hard for me.
I don't look forward to them.
I have Asperger's and I don't...
..like everyone surrounding me.
Before I started school striking, during a long period,
I couldn't move around inside schools
because there was too much stimulation and so I had to go to,
like, a special school where there were, like, five people in my class.
To go from there to this reality, it's just a big contrast.
There are people everywhere and everyone is screaming
and it's quite exhausting.
But it is my moral duty as a human being to do everything I can.
So I don't know... I just have to do it.
Now it may seem like it's only negative but, of course,
I get lots of energy from it, as well.
CROWD CHANTS: Climate crisis!
Now!
On stage, it's OK because then I can go into another character.
CHEERING
Of course, it is very inspiring to see that
so many people actually seem to care about this.
Bonjour, Lausanne.
But it feels like today we've pushed almost as far as we can.
Unless people in power start to actually treat
the crisis like a crisis, we won't get anywhere.
Ca va bien? CHEERS
We could go to the Moon and strike.
That wouldn't change anything.
But that doesn't mean we won't continue.
To the world leaders and those in power,
I would like to say
that you haven't seen anything yet!
CHEERING
And that is the message that we will
bring to the World Economic Forum in Davos next week.
While the great and good begin to gather in Davos, Greta is
venturing into the mountains above the town
to see how the Alps are already being reshaped by climate change.
Oh, my that's big.
In 2017, a rock face above the village of Bondo gave way,
bringing millions of tonnes of boulders
and mud crashing through the streets.
It was so loud and there were stones and mud everywhere.
The entire village cost £60 million to repair.
Eight people lost their lives.
It was terrifying.
Alpine rockfalls are becoming more frequent,
and scientists have been trying to find out why.
I think we can start digging here.
And we'll just take turns digging. Yeah.
So, here?
Greta has joined Dr Marcia Phillips, who studies permafrost -
ground that remains frozen all year round.
And this snow is like old sugar, isn't it? Yeah.
That's a sign it's been there for a long time.
Dr Phillips has found that snow cover has a surprising
effect on the frozen earth.
Now, what we should do is measure the temperature right at the
bottom of the snow cover, and at the top and see if there's a difference.
Here? You can put it in like this, like... Yeah.
Exactly. Yeah.
And just leave it.
I'm going to disappear in here! Yeah.
So, we have zero at the base
and then we'll look at the top here, like this.
Minus 2.1. Still going down.
Yeah, 2.3.
It's now minus 2.8.
This difference in temperature between the ground
and the top of the snow cover shows us that the
snow cover is actually keeping the ground warm. Oh!
I think many would be surprised to hear that. Yeah.
We always think snow is cold, but it's like a big,
thick blanket over the mountain. Yeah.
And it traps the heat in the ground. So it is keeping... Exactly.
..the ground warm.
With more snowfall, do we risk seeing more rockfall, as well?
Snow has a huge influence on ground temperature.
It will influence whether ice in the ground will melt or not.
And it will also influence how much water can actually run into the
ground in spring, when we have snow melt happening up in the mountains.
And water running into rock, or into cracks in the rock,
is very bad, and that can lead to rockfall.
Yeah, at high elevations, they think we're going to get more snow,
which is not so good for the permafrost.
On steep slopes, where snow doesn't settle,
rising air temperatures also play a part.
Warm air causes ice within the rock to melt, and water to seep in,
destabilising the cliff.
So, what worries you about the future?
Zero degrees in the air temperature has
climbed 500 metres in my lifetime and I'm 50 years old.
Oh. So that's a 500 metre difference, which is quite huge.
Um...
It's not very powdery for a snow angel, I think. No.
Whilst rockfalls pose a danger in the mountains, elsewhere,
thawing permafrost has global implications.
The amount of permafrost on the planet is huge.
It's around 15% of Northern Hemisphere land.
Trapped in the soil is lots of organic matter from plants.
As the permafrost thaws,
the organic matter that is frozen in the ground thaws, as well,
and that releases greenhouse gases.
Carbon dioxide, but also methane.
Methane is a potent greenhouse gas. It's actually more effective
at trapping the sun's rays than carbon dioxide is.
So that causes even more warming and more thawing of the permafrost.
It's what called a positive feedback loop, where things get worse
and worse and worse and worse.
It's hard to know how much the permafrost is going to release,
but scientists predict it could release gases equivalent
to between 40 and 700 billion tonnes of CO2 this century.
In a village just outside Davos, Greta is getting
ready for one of her most important speeches to date -
a rare chance to put the case for curbing fossil fuel use
to the world's political and business leaders.
This will be a very intense week.
My schedule is already fully packed.
I probably need to take some things out!
Obviously, we haven't gotten anywhere.
And we are still, like...
What's that? It's a pig.
I found this on the ground in Vienna.
It doesn't take up much space.
One very important person that is going to be there
and that people are talking about is Donald Trump.
President Trump promised voters that he'd bring back coal.
My administration is putting an end to the war on coal.
Going to have clean coal. Really clean coal.
The media has made me to the, like, anti-Trump,
so I am being treated as the opposite of Trump.
So it's me, Greta, versus Trump.
A small, shy girl who's speaking
about science versus Donald Trump.
What happens if you meet him?
I have actually no idea. It depends on the situation.
I can't be rude.
But on the other hand, I can't be too nice.
On the eve of the annual World Economic Forum in Davos,
focus on teenage activist Greta Thunberg is there, as she prepares
to challenge the global financial elite to fight climate change.
The other global figure topping the bill today will be Donald Trump.
Their appearance today is bound to feel like something of a showdown.
What do we want? Climate crisis! When do we want it? Now!
2020 is an absolutely pivotal year for our world's climate.
Some are even calling it the Year of Truth.
We are going to start with some words from Greta Thunberg.
You say children shouldn't worry.
You say, "Just leave this to us.
"We will fix this." And then, nothing.
Silence.
Or something worse than silence - empty words and promises
which give the impression that sufficient action is being taken.
Last week, I met with Polish coal miners who lost their jobs
because their mine was closed.
And even they had not given up.
On the contrary, they seemed to understand
the fact that we need to change more than you do.
I wonder, what will you tell your children was the reason to fail?
We demand participants immediately halt all investments in fossil fuel
exploration and extraction,
immediately end all fossil fuel subsidies
and immediately and completely divest from fossil fuels.
We don't want these things done by 2050, 2030, or even 2021.
We want this done now.
The oil and gas companies themselves
are recognising how much they have to change.
Are they changing fast enough? I don't think so.
We've already found far more fossil fuels
than we can usefully burn to stay within
our international temperature goals -
by some estimates, 15 times the amount.
But fossil-fuel companies are still spending a lot
on exploration - perhaps $55 billion a year or so.
It's incumbent upon governments around the world
to change the rules,
so that you win by being clean
and you lose when you're dirty.
Despite the fact that we know just how damaging fossil fuels are,
governments around the world are still subsidising them.
In terms of the global magnitude of fossil fuel subsidies, it amounts to
around $373 billion US, annually.
It would definitely be helpful if we were able to transfer
some of those subsidies from fossil fuels towards cleaner technologies.
On the same day as Greta's speech, President Trump takes centre stage.
Donald Trump has flown over 4,000 miles from Washington
to the Alpine heights of Davos. The main goal of this meeting,
to do much more to tackle global temperature rise.
It's an honour to address the distinguished members
of this organisation.
The United States is now by far the number one producer of oil
and natural gas anywhere in the world.
The American energy revolution is lowering electric bills
and - very importantly - prices at the pump.
The United States no longer needs to import energy.
But to embrace the possibilities of tomorrow, we must reject
the perennial prophets of doom
and their predictions of the apocalypse.
US President Donald Trump spent several minutes of his speech
hailing the economic importance of the oil and gas industries,
dismissing what he termed "perennial prophets of doom"
on climate change to an audience that included Greta Thunberg.
Mm...
Yeah...
I held the speech and the only thing people were interested in was
Greta versus Trump - what do they say about each other?
But I just ignored him completely.
They just want to make headlines that creates clicks.
What I actually said in the speech goes completely...
..I mean, unnoticed.
If the numbers are being completely left out, um...then...
..we're not getting anywhere.
Greta's father, Svante,
has travelled from Sweden to offer his support.
Now I have the privilege to present
the President of the United States of America, Donald J Trump...
All they were saying was just how great their own country was.
And how great they were.
I mean, that's how you tell the difference between different
kind of leaders. I mean...
If you don't even mention...
..the challenges, then that... It's just...
But it... Yeah. So, like.... Every second is just... Yeah.
But, Greta, you've been saying that for at least two years,
or three years.
What rules the world today is power and arrogance and...
And I think she's just the complete opposite of that.
She's not strong.
I am very emotional,
I am very small and I'm very...
Yeah, I am... I am weak, in a way.
That's something I'm very proud of
because if you are able to live in the society without...
Without feeling
bad, without...becoming depressed, or something...
..then that...
If you...
If you feel bad today,
so many people are so sad and so depressed and, like...
But that's a good thing because that means they still have empathy.
And they... And they don't want to live in this world,
where we have lost empathy.
Yeah, so many people come up to me and say, like, they believe
there is something wrong with them because they are feeling...
Feeling like shit.
But I think it's the opposite.
It's the rest who can maintain living in this...
This society where we only care about prestige
and these shallow things that don't matter and being the best and so on.
Those are the people who...
..who are not normal.
The more I've been able to experience,
the more I realise that this world we are living in right now is
not sustainable, in many different ways.
We have stopped caring what is true or not.
We no longer care for the things that actually matter.
We only care what's on the surface.
And the climate crisis is of course a symptom of that.
Now, we can either choose to continue down this road,
which will lead nowhere - and we know that -
or we can choose to choose a different path.
Greta has travelled to the UK -
a country attempting to establish itself as a climate leader.
The Prime Minister has announced plans
to cut the UK's carbon emissions
to almost zero over the next 30 years,
to help tackle climate change.
The UK is funding research
into technological innovations
to try to limit global warming.
And Greta is here to find out about a multimillion-pound project,
in which they're researching a novel way of tackling emissions.
Many people seem to think that there will be a sort of magic
silver bullet that scientists will invent that easily will fix
the climate crisis, without us actually having to make an effort.
And I want to go to see these solutions in action.
The UK Government's plans include funding for pilot projects,
which aim to help industry reduce its carbon emissions...
..from plants producing hydrogen for vehicles...
..to steel refineries and power stations.
But most of these plans rely on a single technological
breakthrough - carbon capture.
It's currently being trialled at Drax -
a woodburning power station in Yorkshire.
It's the biggest power station in the UK...
CEO Will Gardiner's team is developing the prototype,
designed to remove carbon dioxide from the power plant
before it escapes into the atmosphere.
So this is where we're doing our pilot projects
for our carbon capture.
The waste gas is mixed with a chemical solvent,
which separates the carbon dioxide from the other gases.
The idea here is that each one of these tubes sort of sprays
the solvent in there
and it interacts with the gas inside the column to do the capture.
The prototype currently captures one ton of carbon dioxide each day -
less than 0.01% of the plant's emissions.
To give a sense of scale,
those pipes there are carrying about 10,000 tonnes of flue gas a day
and so the idea would be we need to move from that one to that one.
Right now, you are capturing one ton a day.
What is happening to that carbon?
Where are you storing it?
So, I mean, to be honest, most of what we're capturing today,
we're actually returning into the system
because we don't have the sort of underground storage, it's not ready.
So the idea is that we would build a pipeline from here and take out
the CO2 and stick it under the North Sea and permanently lock it away.
We have to do that as fast as we can.
Approximately when would you be able to capture
as much CO2 as you are emitting?
For us to capture effectively all of it,
it's probably some time in the early 2030s.
And that's the sort of current thinking.
I mean, wouldn't it just be easier to just spend that money on,
for example, building wind turbines or...?
So, the answer is, we need to do both, in my view.
They are moving in the right direction -
and, of course, I admire their determination -
but I have so many mixed feelings about this.
We have to also acknowledge and realise the fact
that emissions need to reduce now, today.
We can't wait for a couple of decades
for these technologies to become available
that will alone solve this problem for us.
There isn't a one-size-fits-all solution to tackling climate change.
Carbon capture and storage technology
is one part of the solution.
It cannot be THE solution.
To really tackle climate change,
we need to adjust, adapt, change almost everything we do.
We need to find technological solutions
to drastically reduce our energy use.
We moved recently from incandescent light bulbs to LED light bulbs,
which are around 90% more efficient than the old ones.
The amount of electricity needed now to do a wash on your washing machine
is considerably less today than it was ten years ago.
These energy savings do make a real difference.
For example, in the UK, although our houses are now
full of all sorts of gadgets and gizmos,
our electricity usage is actually down, compared to the mid-1990s.
In supermarkets, instead of having open fridges,
they can put doors on them.
Supermarket fridges account for around 1%
of total electricity usage in the UK,
so tackling that could have a very significant effect.
But technology alone probably isn't going to find all the solutions.
We need to curb the growth in our total energy use
in order that our renewable energy supply stands a chance of replacing
rather than just being as well as
the fossil fuel that we use.
We've had to actively think about how we use less energy.
Without that, I don't think we can create the necessary change.
To see how she can engage more people with her message,
Greta has come to London.
She's seeking the advice of someone who's been sharing the wonders
of the natural world for over 70 years.
Sir David Attenborough.
Hi. Hi. How are you doing? I'm good. Nice to see you. Nice to meet you.
It's an honour to meet you and thank you for...
I want to ask you, have you during your career
seen any changes in the natural world?
Because you obviously had the opportunity to see it first-hand.
What happened first was that you suddenly realised
that there were animals that had been there once,
and aren't there any more.
The public as a whole thought,
"Well, that's interesting,"
but they didn't actually realise we're changing the world, you know?
Or even consider that we might be changing the climate.
And for a long time, it suited people
to bury their heads in the sand.
But it is to do with us, and we know about the way the world works -
that's what science is about.
We need to reach some kind of tipping point. Mm.
What would you say to people - especially young people -
who feel like there isn't any point in doing this
because no-one is listening anyway?
People are listening.
I mean, there is a precedent, of course.
There was... There was a time 30 years ago
when it really looked as though we might certainly exterminate
several species of big whales.
Fishing nations, maritime nations of the world did get together
and did say, "OK, unless we do something,
"we're going to lose everything."
And there just could be a change in moral attitude
from people worldwide, politicians worldwide,
to see that self-interest...
..is for the past,
common interest is for the future.
We've seen many young people starting to speak up more and more
and to realise the urgency,
but do you have any thoughts or ideas how we can
activate the older generations, as well?
Because we need everyone.
Yes, we do.
My generation has made a mess of things.
We've known that it's happening and we've done nothing.
Or next to nothing.
We have to make major changes to the way we live
and that's where you've done such a lot, you really have.
And you have... You have spoken for
the generation that's going to have to look after this.
I've been bleating about this for a long time,
but the big changes came when you spoke...
..and that's...
That's brought hope.
VOICEOVER: This is a marathon, not a sprint.
I have made a deal with myself that I am in this for the long run
and I can't be discouraged by things not happening
the way I want them to be.
Instead of just being worried and depressed
and speculating about how the future may be,
then you should try to change that future while you still can
in order for that future to turn out the way it should.
Greta has big plans for the next stage of her journey -
a 5,000-mile train ride.
Today, you can't speak up about the climate or environment
without being questioned all the time.
"Just look at China. What about China?"
And so, therefore, I want to at least try to go there
to be able to say, I... "Well, I tried."
But recent events are making the trip more challenging.
It's been confirmed that a new virus that has killed three people
and has been spreading across China can be passed from person to person.
The infection is a new type of coronavirus.
It was coming up in the papers and obviously all the world leaders
were having emergency meetings
and lots of Greta's stuff was being cancelled because, erm...
Erm, yeah, things were changing.
The number of people infected has tripled over the weekend,
with the outbreak spreading to the capital, Beijing.
It's very hard to predict how this is going to evolve...
..erm, the following weeks, months.
I guess I will start planning, like, two weeks at a time.
With her plans on hold, Greta is heading
to the south-west of England.
TANNOY: This is Bristol Temple Meads.
This train terminates here.
She's now halfway through her year off school.
I don't think I'm much different now
but, of course, I've met with many people,
I've talked to many people, which, of course,
have helped shaped the way I see the world.
But, at the same time, I'm still the same person,
still saying the same message over and over again.
She's matured a lot.
She knows what she wants to do
and she knows, erm, how to do it.
And I think she allows herself to enjoy that, too.
I think that's the biggest difference, is that she's...
She's having more fun.
CHEERING
Greta is in Bristol to help local activists celebrate a rare victory.
Controversial plans to expand Bristol Airport
have been thrown out by councillors.
They criticised what the airport's plans would do
both to the local area and the global environment.
Small victories are important because they keep the momentum going
and shows that activism does actually work.
And then people get motivated by that and want to continue.
It's not for nothing.
I am so happy to introduce Greta Thunberg!
CHEERING
Wow. Thank you so much for coming.
VOICEOVER: I don't spend time, like, speculating,
is this really possible?
World leaders are behaving like children,
so it falls on us to be the adults in the room.
VOICEOVER: I know what to do, and I do it until I cannot do it any more.
And every single person counts.
We can't just give up without trying -
only a coward would do that.
And I don't think that we are cowards.
Next time, Greta faces her biggest challenge
as the climate is overshadowed by a more immediate threat...
We may have contracted the coronavirus.
..and she explores more ways we can lower our emissions.
We could store all the emissions we could potentially imagine.
To find out more about climate change and explore what actions
you can take to reduce your environmental impact,
go to...
..and follow the links to the Open University.